Revit Guides
Data Management
ELI5
zone indicator
part of indicating equipment which visually indicates the zone of origin of a alarm of fire or faultwarning BS 4422 2005 Zone Indicator in Fire Alarm Systems The zone indicator
jet reaction
nozzle reactionforce acting in the opposite direction to the water stream leaving the nozzle BS 4422 2005 “Jet reaction,” also known as “nozzle reaction,” is a fundamental concept in fluid
jet
extinguishing medium, usually water, leaving a nozzle as a continuous stream, water spray, or waterfog (mist) BS 4422 2005 Each of these methods has its own advantages and is chosen
Navigating Construction Projects with Incomplete Building Services Design: Real-world Solutions Wanted 🛠️
Here is my list of reasons why so often we have incomplete Building Services Design before the project starts construction: Incomplete Building Services Design (BSD) before the commencement of construction
How to Rotate Revit Families in Any Direction
Mastering 3-Axis Rotation: Transform Revit Face-Based Families with Tiltable Geometry
Exchange Information Requirements (EIR)
The Exchange Information Requirements (EIR) term introduced by BS EN 19650 replaces the PAS 1192 term Employer Information Requirements (EIR) on all projects where BS EN ISO 19650 compliance is
Emergency Lighting in Toilet Cubicles
Summary
1. If the toilet has borrowed light and is less than 8m square:
a. There is no need for emergency lighting, however,
b. If there is a cubicle with full height door – therefore closed without borrowed lighting – then the EM lighting would be required in that cubicle.
2. If the overall toilet has no borrowed light,
a. And the WC cubicles do not have full-size doors; there should be at least one emergency outside row of cubicles.
b. If there is a cubicle with full height door – therefore closed without borrowed lighting – then the EM lighting would be required in that cubicle.
coordination
Coordination goes beyond orderly task execution, it transforms individual perspectives into shared, community-wide actions. It’s not just a subset of collaboration; it’s the engine that makes collaboration more than a patchwork of solo efforts.
Ze
That part of the earth fault loop impedance which is external to the circuit under consideration. For the supply cable it will be the impedance external to the installation. For
Z2
Z2 – That part of the earth fault loop impedance which comprises the impedance under earth fault conditions of the circuit protective conductor (cpc) of the circuit under consideration.
Z1
Z1 – That part of the earth fault loop impedance which comprises the impedance under earth fault conditions of the line conductor of the circuit under consideration.
Uninterruptible power supply (UPS)
An uninterruptible power supply (UPS) is used to maintain the supply to an essential service duringmains supply outages. On loss ofmains supply,a storage device in the UPS (battery) continues to
Nominal line voltage to earth (Uo)
Uo Nominal line voltage to earth. Assumed to be 230 V for grid connected systems.
TT system
A system having one point of the source of energy directly earthed, the exposedconductive-parts of the installation being connected to earth electrodes electrically independent of the earth electrodes of the
TN system
A system having one or more points of the source of energy directly earthed, the exposedconductive-parts of the installation being connected to that point by protective conductors.
Subject to Simultaneous Overload
Where circuits are grouped, there are two availablemethods of calculating the rating factor Cg to be applied: [BS7671:2018,Appendix 4,5.1.2:Equation 2] [BS7671:2018,Appendix 4,5.1.2:Equation 3,4]
Soil Thermal Resistivity
Relates to the ability of the soil, in which the cable is installed, to conduct heat energy away from the cable. The rating factor Cs is applied in cable sizing
Residual Current Device (RCD)
AResidual Current Device (RCD) is amechanical switching device or association of devices intended to cause the opening of the contacts when the residual current* attains a given value under specified
Rating factors
Rating factors are divided into the nominal rating of the circuit protective device (In) to determine theminimum current-carrying capacity (Iz) of a cable in a circuit. For example:Iz = In/(Ca
Rated current
Value of current used for specification purposes,established for a specified set of operating conditions.
Power factor
Power factor is the ratio of the resistance (R) and impedance (Z) in a circuit, that is:Power factor = cos ∅ =R/Z
Max Zs
Themaximum value of earth fault loop impedance (Zs) that will allow the protective device in a circuit to disconnect an earth fault within the prescribed time. Example: if themaximum earth
k Factor
Factors for conductor materials from BS7671:2018,Table43.1. Different values are given for different types of conductor and insulatingmaterials. k2s2 used in adiabatic calculations gives the short-time withstand of a conductor in
Current carrying capacity of a cable (Iz)
Iz The current carrying capacity of a cable under the defined installation conditions. This is the effective rating of the cable after the relevant rating factors have been applied, i.e.,Ca,
Overload rating (Ir)
Ir The adjusted overload rating of an overcurrent protective device, in Amperes.
Prospective fault current (Ipf)
Prospective Fault Current (Ipf) is the value of overcurrent at a given point in a circuit resulting from a fault of negligible impedance between live conductors having a difference of
energy let-through of a device (I2t)
I2t The energy let-through of a device in A2s. The total amount of energy let through by a protective device for a given level of fault current at a stated
Harmonic
The presence of harmonic content in the line conductors of a three-phase and neutral circuit can give rise to excessive levels of load current in the neutral conductor.
Fixed Equipment
Equipment designed to be fastened to a support or other wise secured in a specific location.
Final Circuit
A circuit connected directly to current-using equipment, or to a socket-outlets or other outlet points for the connection of such equipment.
